SRD:Gem of Brightness

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Gem of Brightness: This crystal appears to be a long, rough prism. Upon utterance of a command word, the crystal emits bright light of one of three sorts.

One command word causes the gem to shed light as a hooded lantern. This use of the gem does not expend any charges.

Another command word causes the gem of brightness to send out a bright ray 1 foot in diameter and 50 feet long. This strikes as a ranged touch attack, and any creature struck by this beam is blinded for 1d4 rounds unless it makes a DC 14 Fortitude save. This use of the gem expends 1 charge.

The third command word causes the gem to flare in a blinding flash of light that fills a 30-foot cone. Although this glare lasts but a moment, any creature within the cone must make a DC 14 Fortitude save or be blinded for 1d4 rounds. This use expends 5 charges.

A newly created gem of brightness has 50 charges. When all its charges are expended, the gem becomes nonmagical.